This invention relates to atomizing spray nozzles and more particularly to a nozzle which uses air or other gas under pressure for liquid atomization at a supersonic-subsonic transition region, together with means for applying two or more liquid phases to be intimately atomized, dispersed and intermixed with each other.
There is a need for nozzles which have the capability or function of mixing two-part or multi-part liquid materials at a region outside of the nozzle, so that the materials, which may be reactive or which may interact with each other, may be delivered and metered independently and separately to the exit regions or orifices of the nozzle for the purpose of mixing and atomization. Such a nozzle should mix two-part materials without the use of a separate dynamic or in-line motionless mixer. The present invention is an improvement applied to the nozzles described and claimed in the U.S. Pat. Nos. of Cresswell, 3,741,484 issued June 26, 1973 and 3,923,248 issued Dec. 2, 1975. In the Cresswell patent disclosures, which are incorporated herein by reference, air or gas atomizing nozzles have a single outer annular ring or layer of liquid applied to a deflector or distributor and broken up by an inner layer of gas expanded to a supersonic velocity over the outer surface of the deflector. The acoustic shock wave created at the sonic transition further causes a break up of the particles.